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eagle

Please explain how a mixmatched ( 13 & 10 ) would cause those pressures ? If they are the same size units, and if the outdoor was 13 seer, why would the pressures be so high, and why would someone have overcharged it.
Can you give us the press / temps after repair??

This was a new install,indoor and outdoor.According to the lennox tech support guy,a 13 seer unit holds more refrigerant than a 10 seer indoor coil can handle.I will keep you posted when we change out the air handler.

Sorry, But I respectfully disagree Lynn, the accumulator is there to prevent liquid from hammering the compressor and there is an oil return port that also returns a small amount of liquid to be fed which should be overcome by superheat. An accumulator is not storage.

I'm quoting a pretty good description from HVAC NEWS...9/3/01

The suction line accumulator is a temporary reservoir for this mixture (refrigerant and oil), designed to meter both the liquid refrigerant and oil back to the compressor at an acceptable rate. This prevents damage to the reed valves, pistons, rods, and crankshafts.

Accumulators have a metering ejector device that picks up liquid, vaporizes it, and returns it to the compressor. This prevents liquid slugging and controls oil return. It is particularly important on hot gas defrost systems, heat pumps, etc., where surges of liquid refrigerant frequently go back down the suction line.

Now, yes you will on occasion find liquid refrigerant there but as we all know the suction side of the system is never a place for liquid refrigerant.

But at our last HP training meeting the trainer stated Lennox systems need to be matched. Other's equipment use the accumulator to store the excess refrigerant in the winter. I don't think matching AH and OU is as critical with other brands.